C/2023 P1 (Nishimura)
メタデータ
| 項目 | 値 |
|---|---|
| Designation | C/2023 P1 (Nishimura) |
| Type | C |
| Perihelion (tp_cal, UTC) | 2023-09-17T15:23:38.446080Z |
| Orbit solution date (soln_date, UTC) | 2024-08-08T14:27:14Z |
| Obs used | 638 |
| NEO | - |
| M1 | 12.200 |
| K1 | 8.000 |
| PC | - |
| Discovery observation (MPC, UTC) | 2023-08-11T18:26:41.856000Z |
| Discovery magnitude (MPC) | 11.00 T |
| Discovery observatory (MPC) | 247 · Roving Observer |
オスキュレーティング軌道要素
| 項目 | 値 |
|---|---|
| Epoch (epoch_cal, TDB) | 2023-09-08.0000000 |
| e | 0.99610274 |
| q (au) | 0.225152 |
| a (au) | 57.771776 |
| i (deg) | 132.476418 |
| Ω (om, deg) | 66.834552 |
| ω (w, deg) | 116.297994 |
| M (ma, deg) | 359.978359 |
等級
散乱 + 全体線形
$$ M_a = (10.942 + 5.265\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
モデル定数
| 項目 | 値 |
|---|---|
| H0 | 10.942 |
| n | 5.265 |
| gf | 0.997 |
| gb | -0.921 |
| k | 0.944 |
| δ90 | 9.998 |
| パラメータ | 記号 | 範囲 | 説明 |
|---|---|---|---|
| 太陽・地球距離が1 AUのときの絶対等級 | H0 | -5 to 20 | 彗星の固有の明るさ |
| 測光スロープパラメータ | n | 2 to 6 | 太陽距離に対する明るさ変化率 |
| 前方散乱非対称係数 | gf |
0.8 to 1 | 前方散乱の強さ |
| 後方散乱非対称係数 | gb |
-1 to -0.5 | 後方散乱の強さ |
| 分配係数 | k | 0.8 to 1 | 前方/後方散乱の寄与比 |
| ダスト/ガス明るさ比 | δ90 | 1 to 10 | ダスト散乱とガス放射の相対寄与 |
参考: EPSC-DPS2025-160
残差 (区間線形)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| 開始日 (UTC) | 終了日 (UTC) | a | b |
|---|---|---|---|
| 2023-01-19 | 2023-09-16 | +0.1403 | +0.148 |
| 2023-09-18 | 2024-05-28 | -0.5521 | -1.485 |
log10 r = log10(太陽距離/AU)、Δ = 地球距離(AU)
天体暦
| Date/Time (UTC) | RA (J2000) | Dec (J2000) | Nearest HIP | Dist from HIP (arcmin) |
|---|---|---|---|---|
| 2026-05-12 00:00 | 08:11:09.70 | -27:47:48.3 | HIP 40139 | 18.69 |
| 2026-05-12 12:00 | 08:11:13.71 | -27:45:55.0 | HIP 40139 | 16.61 |
| 2026-05-13 00:00 | 08:11:17.82 | -27:44:02.5 | HIP 40139 | 14.53 |
| 2026-05-13 12:00 | 08:11:22.02 | -27:42:10.7 | HIP 40139 | 12.45 |
| 2026-05-14 00:00 | 08:11:26.30 | -27:40:19.7 | HIP 40139 | 10.37 |
| 2026-05-14 12:00 | 08:11:30.68 | -27:38:29.6 | HIP 40139 | 8.30 |
| 2026-05-15 00:00 | 08:11:35.14 | -27:36:40.2 | HIP 40139 | 6.23 |
| 2026-05-15 12:00 | 08:11:39.68 | -27:34:51.6 | HIP 40139 | 4.17 |
| 2026-05-16 00:00 | 08:11:44.32 | -27:33:03.8 | HIP 40139 | 2.11 |
| 2026-05-16 12:00 | 08:11:49.04 | -27:31:16.8 | HIP 40139 | 0.30 |
| 2026-05-17 00:00 | 08:11:53.84 | -27:29:30.6 | HIP 40139 | 2.06 |
| 2026-05-17 12:00 | 08:11:58.73 | -27:27:45.2 | HIP 40139 | 4.12 |
| 2026-05-18 00:00 | 08:12:03.70 | -27:26:00.7 | HIP 40139 | 6.17 |
| 2026-05-18 12:00 | 08:12:08.75 | -27:24:17.0 | HIP 40139 | 8.23 |
| 2026-05-19 00:00 | 08:12:13.89 | -27:22:34.1 | HIP 40139 | 10.28 |
| 2026-05-19 12:00 | 08:12:19.10 | -27:20:52.1 | HIP 40139 | 12.34 |
| 2026-05-20 00:00 | 08:12:24.40 | -27:19:10.9 | HIP 40139 | 14.39 |
| 2026-05-20 12:00 | 08:12:29.78 | -27:17:30.5 | HIP 40139 | 16.44 |
| 2026-05-21 00:00 | 08:12:35.23 | -27:15:51.0 | HIP 40139 | 18.49 |
| 2026-05-21 12:00 | 08:12:40.77 | -27:14:12.3 | HIP 40139 | 20.54 |
| 2026-05-22 00:00 | 08:12:46.38 | -27:12:34.5 | HIP 40139 | 22.59 |
| 2026-05-22 12:00 | 08:12:52.07 | -27:10:57.5 | HIP 40139 | 24.64 |
| 2026-05-23 00:00 | 08:12:57.84 | -27:09:21.4 | HIP 40370 | 26.02 |
| 2026-05-23 12:00 | 08:13:03.68 | -27:07:46.2 | HIP 40370 | 26.02 |
| 2026-05-24 00:00 | 08:13:09.59 | -27:06:11.8 | HIP 40370 | 26.16 |
| 2026-05-24 12:00 | 08:13:15.58 | -27:04:38.3 | HIP 40370 | 26.44 |
| 2026-05-25 00:00 | 08:13:21.64 | -27:03:05.7 | HIP 40370 | 26.85 |
| 2026-05-25 12:00 | 08:13:27.78 | -27:01:33.9 | HIP 40370 | 27.38 |
| 2026-05-26 00:00 | 08:13:33.98 | -27:00:03.0 | HIP 40370 | 28.03 |
| 2026-05-26 12:00 | 08:13:40.26 | -26:58:32.9 | HIP 40370 | 28.80 |
| 2026-05-27 00:00 | 08:13:46.61 | -26:57:03.8 | HIP 40370 | 29.67 |
| 2026-05-27 12:00 | 08:13:53.03 | -26:55:35.5 | HIP 40370 | 30.63 |
| 2026-05-28 00:00 | 08:13:59.52 | -26:54:08.1 | HIP 40370 | 31.68 |
| 2026-05-28 12:00 | 08:14:06.08 | -26:52:41.6 | HIP 40370 | 32.80 |
| 2026-05-29 00:00 | 08:14:12.70 | -26:51:16.0 | HIP 40370 | 34.00 |
| 2026-05-29 12:00 | 08:14:19.39 | -26:49:51.3 | HIP 40370 | 35.26 |
| 2026-05-30 00:00 | 08:14:26.15 | -26:48:27.4 | HIP 40370 | 36.57 |
| 2026-05-30 12:00 | 08:14:32.97 | -26:47:04.5 | HIP 40370 | 37.94 |
| 2026-05-31 00:00 | 08:14:39.87 | -26:45:42.4 | HIP 40370 | 39.35 |
| 2026-05-31 12:00 | 08:14:46.82 | -26:44:21.3 | HIP 40370 | 40.80 |
| 2026-06-01 00:00 | 08:14:53.84 | -26:43:01.0 | HIP 40370 | 42.29 |
| 2026-06-01 12:00 | 08:15:00.92 | -26:41:41.6 | HIP 40611 | 40.68 |
| 2026-06-02 00:00 | 08:15:08.07 | -26:40:23.1 | HIP 40611 | 38.62 |